Communication Apparatus, Control Method, and Storage Medium

1. A communication apparatus comprising: a communication unit configured to perform Near Field Communication; a detection unit configured to detect a partner apparatus that exists within a communicable range of the communication unit; a determination unit configured to determine, in the case where the communication unit transmits a first signal, whether or not the communication unit has received a response to the first signal; and a control unit configured to control, in the case where the partner apparatus is detected by the detection unit and it is determined by the determination unit that the communication unit has not received the response to the first signal, the communication unit to transmit a second signal that has a higher amplitude than the first signal and a higher power than the first signal, wherein the second signal is a signal that is of a different type from the first signal and is for causing the partner apparatus to transition into a state in which the partner apparatus can respond to the first signal, and wherein the communication unit performs wireless communication with the partner apparatus in the case where the communication unit has received the response to the first signal from the partner apparatus after transmission of the second signal.

2. The communication apparatus according to claim 1 , wherein the second signal is a signal for causing the partner apparatus to transition from a first state that is a power-saving state to a second state in which a greater amount of power is consumed than in the first state.

3. The communication apparatus according to claim 2 , wherein the second state is a state in which the partner apparatus can communicate with the communication apparatus.

4. The communication apparatus according to claim 2 , wherein the partner apparatus transitions from the first state to the second state in response to receiving a signal having no less than a predetermined power level.

5. The communication apparatus according to claim 2 , wherein the partner apparatus transitions from the first state to the second state in response to receiving a signal that cannot be demodulated.

6. The communication apparatus according to claim 1 , wherein the second signal is a signal amplified in a non-linear region of an amplifier.

7. The communication apparatus according to claim 1 , wherein the detection unit detects the partner apparatus by determining whether or not an impedance of an antenna that carries out communication has changed.

8. The communication apparatus according to claim 1 , wherein the detection unit detects the partner apparatus by determining whether or not a current in an antenna used for carrying out communication has changed.

9. The communication apparatus according to claim 1 , wherein the control unit controls the communication unit to transmit the first signal after transmitting the second signal, and to retransmit the second signal in the case where the communication unit has not received the response to the first signal from the partner apparatus.

10. The communication apparatus according to claim 9 , wherein, when the communication unit retransmits the second signal, the control unit controls the communication unit to increase a power level of the second signal and to retransmit the second signal.

11. The communication apparatus according to claim 9 , wherein the control unit controls the communication unit to stop transmitting the second signal in the case where a number of times the second signal has been transmitted has reached a predetermined number.

12. The communication apparatus according to claim 1 , wherein in the case where the communication unit has received the response to the first signal from the partner apparatus before transmission of the second signal, the communication unit communicates with the partner apparatus without transmitting the second signal.

13. The communication apparatus according to claim 1 , wherein the first signal is a polling signal.

14. A control method for a communication apparatus that comprises a communication unit configured to perform Near Field Communication, the method comprising: detecting a partner apparatus that exists within a communicable range of the communication unit; determining, in the case where the communication unit transmits a first signal, whether or not the communication unit has received a response to the first signal; and controlling, in the case where the partner apparatus is detected and it is determined that the communication unit has not received the response to the first signal, the communication unit to transmit a second signal that has a higher amplitude than the first signal and a higher power than the first signal, wherein the second signal is a signal that is of a different type from the first signal and is for causing the partner apparatus to transition into a state in which the partner apparatus can respond to the first signal, and wherein the communication unit performs wireless communication with the partner apparatus in the case where the communication unit has received the response to the first signal from the partner apparatus after transmission of the second signal.

15. A non-transitory computer-readable storage medium storing a computer program that causes a computer in a communication apparatus that comprises a communication unit configured to perform Near Field Communication to: detect a partner apparatus that exists within a communicable range of the communication unit; determine, in the case where the communication unit transmits a first signal, whether or not the communication unit has received a response to the first signal; and control, in the case where the partner apparatus is detected and it is determined that the communication unit has not received the response to the first signal, the communication unit to transmit a second signal that has a higher amplitude than the first signal and a higher power than the first signal, wherein the second signal is a signal that is of a different type from the first signal and is for causing the partner apparatus to transition into a state in which the partner apparatus can respond to the first signal, and wherein the communication unit performs wireless communication with the partner apparatus in the case where the communication unit has received the response to the first signal from the partner apparatus after transmission of the second signal.